Exposure Calculator vs Night Camera HD

Takes the guesswork out of what shutter speed to use. Ever struggled with an exposure meter or the camera's auto exposure system and found that it just cannot seem to determine the correct shutter speed? I have and that is why this App was written. There are tables and formulae to help you to work out the shutter speed for yourself, but that's not easy. This App takes some simple information about the lighting conditions, the f-stop of the camera and the ISO rating being used and calculates what the correct shutter speed should be. It is that simple. If you have used the pre-calculated tables before you might be suprised by the answers this App gives you but, believe me, I have implemented the formulae and the pre-calculated tables are approximations (sometimes rather wild ones). The tables do not include all f-stops, the tables do not take account the different ISO values cameras can be set to. This App does. This App takes this information and presents it in an easy to use form. Just type in the f/stop value using the keypad, type in the ISO rating using the keypad and then select the applicable lighting conditions from the four lighting condition types: Daylight, Twilight, Night and Indoors. Each has a range of Exposure Values to select from. The App then calculates what the effective EV value is (given the ISO rating) and so can calculate what the actual shutter speed should be. It also shows the applicable row from the standard tables for the EV. Depending on the ISO rating being used the Exposure value selected from the list can be increased or decreased e.g. if the light is low and the EV is -3 but you are using ISO 800 then the effective Exposure value is zero (ISO 800 counts as +3 to EV) the shutter speed needs to match this value not that selected from the standard lighting condition values. The tables only show some of f/stop values. For example the tables show f/2.0 and f/2.8 but you might have the camera set to f/2.4. Well it is possible to calculate the exact value so this is what the App does. Coupled with ISO values that do not generate exact EV numbers this value can show you the true value you should be attempting to use. An ISO of 250 adds +1.32 to the EV value. It is a log2 scale. Now you may not be able to set you camera to the exact value given but it does give you a much better idea of the real shutter speed required rather than trying to guess from the tables (which are calculated on a logarithmic scale and are approximations). By being able to set the ISO to 250 or 500, etc this App is can calculate the real EV value. If you set the ISO to 1000 then any EV value selected needs to have approximately 3.3 added to it to give the correct EV value. So if the selected EV is 6 then the effective EV with this ISO is actually 9.3. But there is no row for 9.3 in the standard tables and it does make a difference. If the camera is set to f/3.5 then the closest row in the table is for EV9 and f/2.8 (1/60th of a second) or f/4.0 (1/30th of a second). So do you err towards 1/30th or 1/60th. Well this App actually calculates the exact value and this shows as 1/52nd of a second. Generally a camera cannot be set to this but it can be set to 1/50th so I would try that and then maybe 1/60th and maybe 1/40th. The calculation comes out as 1/50th because the EV is not 9 it is 9.3 and therefore with the ISO at 1000 everything must be treated as brighter and so less exposure is needed. Being able to see the exact value to use is even more use when long exposures are needed. The standard tables get very vague for low light conditions i.e. EV -6 for f/22 is 64 minutes and for f/32 it is 128 minutes (over an hour more). So if you are using f/28 how many minutes at ISO 1250? Well the answer is 66.9 minutes which is much shorter than you might have guessed.

Night Camera HD - the expert for professional nighttime shots on iPhone, iPad and iPod touch. AppAdvice 4.5/5 stars review: "Night Camera HD is a tool that every inclined mobile photographer should have." Thanks to the manual setting options for light exposure up to 1 second *, separate residual light- and ISO enhancement, Night Camera HD is perfect for taking pictures in a dark, insufficiently lit environment. Even during daylight, your pictures are clearer, with less interference, due to the extended exposure times. Take high-resolution photos in PNG format without visual loss. Forget about the loss of quality experienced with other cameras apps caused by image compression artifacts. Regardless whether you take night-, scenery- or other photographs, the picture quality you are able to achieve with Night Camera HD will surprise you. You can easy tap to focus and tap to exposure at the same time. After selecting the desired setting, you can easily lock it to prevent changes despite movement. Only here you can get luminance, luminosity and RGB histograms in real time to recognize over- and underexposure in time. The self-timer, which is imperative for nighttime shots, enables you to take un-blurred pictures. With the aid of the volume buttons you can take pictures with volume up (+) and fade the HUD-elements in- and out with volume down (-). Of course you can also block the white balance separately and edit it if necessary. Standard image formats (4:3, 3:2, 1:1, 16:9 and 3:1) can be edited live. The full-screen mode is activated for narrow image formats, enabling maximum display use. This feature can also be deactivated. The histogram adapts to all image formats. The up to 6x digital live zoom can be edited in the settings to enable a greater precision level during targeted zooming. Of course diverse alignment grids (e.g. Rule of Thirds, Golden Spirals and Golden Triangle) as well as a virtual horizon are available as overlays. Various real-time color filters complete this app. The most important functions: - Shutter speed control - Up to 1 second * exposure time - Manual ISO setting - Manual focus - Residual light enhancement - Real-time luminance histogram - Real-time luminosity histogram - Real-time RGB histogram - Self-timer - Volume Up (+) Photo Capture - Volume Down (-) HUD Hide - 6x digital live zoom - Tap to focus - Tap to exposure - White balance-lock - Manual white balance - Manual exposure adjustment - Various alignment grids - Virtual horizon - Aspect ratios: 4:3, 3:2, 1:1, 16:9 and 3:1 - Full-screen mode - Eco mode - Diverse color filters in real-time - Take HD photos - Landscape and portrait mode - Supports front and back camera - Supports LED-continuous light - Supports EXIF-data - Supports sharing via Facebook, Twitter *) Only on supported devices ---------- Please note that a minimum amount of light is still required. For delayed exposure times the preview is also delayed accordingly. We recommend stabilizing the device or a steady hand for taking optimal pictures with long light exposure times. ---------- Follow @NightCameraHD on Twitter and don’t forget to tag your photographs with #NightCameraHD. "Night Camera HD" is available on Facebook as well. We are looking forward to requests, suggestions and above all, Likes. Of course an iPad Version is available as well. Just search for "Night Camera HD" in the iPad App Store. Follow us: http://twitter.com/NightCameraHD Like us: http://www.facebook.com/NightCameraHD Visit us: http://www.clidoapps.com